Archives de l'Institut Pasteur de Madagascar最新文献

The effect of two different insecticides on flea control was tested from January to March 2000 in the Ivory village and the Ambatolahy village: Knox-Out, a microcapsulated formulation of diazinon, organophosphorous compound (240 gr/L) and the deltamethrin powder (2 g/kg ai), respectively. The villages are located 2.5 km apart in the Betafo region in Madagascar. Deltamethrin is a pyrethroid and is still used in the National Plague Control Program, whereas diazinon has not previously been applied in plague control in Madagascar. The flea index and the prevalence of rats carrying fleas in the two villages before and after (at one and two months follow-up, respectively) were measured to evaluate the effect of each insecticide. Flea index decreased significantly in both villages by at the first month follow-up. However, at the second month follow-up no significant differences in comparison to pre-treatment index values were observed in any of the villages. This study has demonstrated a similar immediate effect of deltamethrin and of diazinon, and confirmed the absence of remanent action of the two insecticides.

Tuberculosis is worldwide considered as a major health problem with high morbidity and mortality rates. Diagnosis of tuberculosis can be problematic. Microscopy, as the basic diagnostic method, stands inadequately alone due to a low sensitivity, and culture suffers from being time-consuming. A rapid, sensitive and simple diagnostic test, applicable in the field is therefore highly needed. A diagnostic method for the detection of M. tuberculosis by immunocapture technique has been developed using magnetic beads coated with polyclonal anti-M. tuberculosis. The detection of captured bacilli using biotinylated anti-APA monoclonal antibody (APA is a minor secreted antigen) was found more sensitive than microscopy. The results suggest that the development of a rapid strip test to detect major antigen could be a useful tool for the control of tuberculosis.

Neurocysticercosis is the most frequent parasitosis of central nervous system in the world. Neurological manifestations are in relation with locations number and topography, inflammatory reactions level and state of development of the parasite. Epilepsy is the main revealing symptom. Among other neurological manifestations, chronic headache, focal neurological signs, ataxia, language and behaviour disorder are the most anecdotal. The authors report a case of neurocysticercosis in a 71-year-old man with dysarthria and memory problems. Suspected by computed tomography, diagnosis was confirmed by immunoserologic assays such as enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunoelectrotransfer blot assay (EITB). This later emphasized on active form of the cyst. Specific treatment used albendazole as antihelminthic drug. Clinical evolution was good: neuroimaging and immunoserology results were normal respectively 2 and 6 months after the drug therapy.

Toxoplasmosis infection is commonly asymptomatic, but it may have severe teratogenic consequences. The authors review the literature on serologic screening in the first trimester of pregnancy.

In 1994, Médecins du Monde opened a free health centre specialized in STD/AIDS in an ill-favored district of Antananarivo, the Malagasy capital of Madagascar. Besides the medical treatment of Sexually Transmitted Diseases (STD) and AIDS, the centre is responsible for the Information, Education and Communication activities (IEC) within and without the centre towards the residents of the 67 hectares district and the high-risk populations (prostitutes, truck-drivers and transvestites). The project aimed at both preventing the spreading of the VIH infection and reducing the incidence of STD. As the Ministry of Health directed, a syndromic method was applied since 1997 regarding STD. Results for 1998 showed the predominance of the association Neisseria gonorrhae-Chlamydiae among the consultants of both sexes. Negative results from 1,218 HIV serological tests carried out seemed confirm the low prevalence of the HIV infection in Madagascar. Yet, the percentage of positive syphilis serology among the tested consultants was lower than that mentioned in previous surveys. Finally, it appears that the syndromic method is of high interest for the countries with limited laboratory capacities.

Pathological samples issued from patients suspected of extrapulmonary tuberculosis were examined in Laboratories of Mycobacteria and of Histopathology at the Androva Hospital in the University Hospital Centre of Mahajanga. A retrospective study was carried out from 1989 to 1993. During this period, 64 cases of extrapulmonary tuberculosis were recorded. Samples came from Androva Hospital, from Lutherian Hospital of Antanimalandy and from the Medical Centre of Mahabibo. The sex-ratio was of 1.28/1, mean age was 28 years old (extreme ages: 1-78 years old). The diagnosis was confirmed by bacteriological and/or histopathological examinations. Ganglial tuberculosis were the most frequent (53.1%), then digestive tract tuberculosis (20.2%) and anal fistula tuberculosis (14%). In front of chronic lesions, biopsies must be performed to obtain confirmation of diagnosis.

Child meningomyeloradiculitis is a rare complication form of schistosomiasis, even in hyperendemic area. Its diagnosis is very difficult, especially if there are not history or signs of Schistosoma mansoni or hematobium infections. It must be evocated in case of acute flask paralysis occurring in children living in Schistosoma infections endemic area. The authors report a 14-year-old boy's case and suggest etiopathogeny of the disease.

The authors report the results of a randomized epidemiological survey aiming to assess the sero-prevalence of plague in the general population > or = 2-year-old in Mahajanga. In 656 sera tested (by ELISA), the prevalence of anti-F1 antibodies was found to be 6.1%@1000 inhabitants, close to the expected prevalence in the area, where plague reappeared in 1991 after 62 years of absence. The study also demonstrated that the shrew, Suncus murinus, is an important reservoir in the plague transmission in Mahajanga.

In the framework of the poliomyelitis program eradication, the World Health Organization suggests two markers to survey the circulation of the poliovirus: notification of all cases of acute flask paralysis (AFP) and etiological research of these AFP from two stool samples. The authors reported the case of a AFP, occurring after a polio vaccination in a 5-year-old boy who had later an acute rhinopharyngitis treated by antibiotics and quinine intramuscular injections. A left lower limb AFP justified his hospitalisation. The isolation of a Sabin type 3 poliovirus was a pitfall because clinical and complementary investigations demonstrate a peripheral neuromuscular paralysis. This demonstrative case shows the need for health staff to be trained to perform correctly an usual act like intramuscular drug injections.

In 1991, Anopheles gambiae and Anopheles funestus, the main malaria vectors in the Highlands of Madagascar, were reported to be fully susceptible to DDT; nevertheless a slight decrease in the susceptibility levels was recorded when compared with previous assays carried out in 1962. From 1993 to 1997, five cycles of indoor residual spraying have been carried out in the Highlands: a total of 1,482,000 kg of 70% wp DDT have been used for the treatment of houses and animal shelters. From 1996 to 1999, adult mosquito susceptibility tests to DDT and to some pyrethroids (lambdacyalothrine, deltamethrine, permethrine and cyfluthrine) have been carried out on samples collected in 20 areas of the Highlands. Bioassays were carried out following the WHO standard method. All tested populations of An. funestus showed a full susceptibility to DDT. An. gambiae showed a widespread decrease in the susceptibility to DDT, particularly marked in the region of the capital city Antananarivo. Both species were susceptible to pyrethroids.